The process of building a decision model that captures the important relationships of a decision situation is generally recognized as the most time consuming and difficult aspect of decision analysis. This report documents research designed to develop aids for facilitating the model-building process. The ultimate goal of this research is a design for a man-machine system that will help a task force commander and his staff structure the relevant factors of a decision into a formal decision model. The research has resulted in the specification of a structuring process composed of four basic structuring functions: decision bounding, preliminary structuring, model expansion, and model contraction. A preliminary computer program for assisting a task force commander and his staff in applying the structuring process has been developed. Testing and further development of algorithms and computer support for the structuring process is recommended.